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O. D. ROGERS.

DIE FOR FORMING SGREW HEADS.

No. 389,166. Patented Sept. 4, 188.

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UNITED STATES PATENT Qrrrcn.

CHARLES D. ROGERS, OF PROVIDENCE, RHODE ISLAND, ASSIGNOR TO THE AMERICAN SOBEWV COMPANY, OF SAME PLACE.

DIE. FOR FORMING SCREW-HEADS.

SPECIFICATION forming part of Letters Patent No. 389,166, dated September 4, 1888.

Serial No. 243,672. (No model.)

To all whom it may concern.-

Be it known that I, CHARLES D. ROGERS, a citizen of the United States, residing at Providence, in the county of Providence and State of Rhode Island,have invented certain new and useful Improvements in the Method of Making the Heads of lVood-Screws; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will to enable others skilled in the art to which itappertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon,whieh form a part of this specification.

My invention relates to an improved process in the manufacture of wood-screws.

In the manufacture of wood screws as heretofore commonly made the heads are formed by four distinct operations in two separate 2:) machines. One of these machines is called a headingmachine or header, and in it one end of a wire or bar which is to be converted into a screw is upset or forged in a die to a required form by the action of the heading-hammer, so called,which forces the metal to fill the cavity between the die and the face of the hammer. Sometimes two hammers are employed, the first one partially upsetting the metal; but the final form is given mainly 0 by the action of the second hammer. The face of the second hammer is the counterpart of the face or end of the head of the screw, with the exception of the slot, a cavity being formed in it when the face of the screw-head 5 is to be round or globular. The blank with the head thus formed is then taken to another machine in which the head is shaved to give it the precise shape and size required and a finished surface. A slot to receive a screw 0 driver is then, in the same machine, cut by a suitable tool across the face of the head. After the slot is cut the head is submitted again, in the same machine, to the shaving operation to remove the burr formed in cutting the slot. It is obvious that if a finished head can be produced by the use of the heading-machine alone the second machine-that is, the shaving and nicking machine wonld not be required, and the expense attending its use and the waste of metalwould be avoided, such waste of metal amounting fully to one-twelfth of the stock required for a screw.

To secure these results is the object of my invention herein described.

Machines for operating two heading-hammers and the devices forintroducing the wire to the die, holdiugit against the action of the hammers, and removing it from the die when the upsetting is effected are well known and need not be here described. The dies required to form finished heads are those known as solid dies, for the reason that with open dies, so called, a mark of the line at the junction of the two parts of the die will show on the surface of the head. The screw- 6 heads, which will be first referred to and rep resented herein, are the common conical heads with flat faces and slots in the faces.

In the drawings, Figure 1 shows a section of a solid die. The conical cavity, which is the counterpart of the conical surface of the screw-head to be produced, is shown at a. The wire which is to be upset is represented by b, and the head of the hammer which is first to act upon it is represented above it by c. In 5 Fig. 2 the same parts are represented after the hammer has been forced down upon the Wire and die. The upset metal, nearly filling the cavity of the die, is represented at d. An unfilled space at the angle of the die and the hammer is shown at a. In Fig. 3 the same die is represented and the wire and completely-formed head by I) and e. The second hammerhead, f, differs from the first hammer, c, in having a tongue extending from its face, which is the counterpart of andis to produce the slot in the face of the screw. It and the slot are indicated by the dotted lines 9 in Fig. 3. Fig. l is a plan of the end of the wire in the die before it is upset. Fig. 5 is a plan 0 of the partially-formed head and die after the action of the first hammer, as represented in Fig. 2. In Fig. 6 the face of the completed screw-head is shown, the slot being indicated by h. Fig. 7 is a perspective view of the par- 5 tially-formed screw-head removed from the die represented in Fig. 2 after the action of the first hammer. Fig. 8 is a perspective view of the completely-formed screw-head. Fig. 9 is a perspective view of the second hammer. roo

Fig. is a sectional view of a die and hammer adapted to produce a rounded head on the end of ascrew, the slot-forming tongue being wholly within the hammer-cavity; and Fig. 11 is an inverted plan view of the hammer, showing the cavity and tongue.

It will be observed in Fig. 2 that though the face of the hammer c is brought down onto the face of the die there is an unfilled space, a, at the angle of the conical surface of the die with the molding part of the face of the hammer. This unfilled space will extend completely around the die, as shown in Fig. 5. In Fig. 3 the cavity of the die is represented as completely filled by the head 0. It is obvious, therefore, that the unfilled space a between the cavity of the die and the face of the hammer after the action of the first hammer must be equivalent to the space occupied by the tongue 9 on the face of the second hammer. It is equally obvious that the amount of the metal of the wire passed through the die A for the action of the first hammer, 0, must be just sufficient to fill the cavity between the die and the second hammer when they are in contact- If the amount is not sufficient to fill the cavity, the head of the screw will be imperfect. If it is too great, the excess will be forced out between the opposed faces of the die and the hammer, and it will prevent the hammer from closing upon the die, and will also form a fin around the head, which must be subsequently removed.

It will be observed that the first hammer brings the head, except at the angle of the die and hammer, nearly to the form, with the exception of the slot, which it is to have finallythat is, the head has at the edge the form of the conical surface a of the die, and its face has the form, with the exception of the slot, of the opposite portion of the face of the hammer, as clearly shown at d, Figs. 2and 7. This hammer does, therefore, the work substantially which has heretofore been done by the common heading-machines; butin addition to this I provide another hammer, f, which, by means of a tongue, 9, Fig. 9, forms the slot, and which also finishes the head at the angle of the die and the hammer, and by correcting any disturbance of the face of the head caused by the action of the tongue in'entering the metal finishes the face of the head, and thus gives it the precise shape and size required. It does,

therefore, substantially the work of the shavecale ing and nicking machine in the old method of forming heads. In order to do this, however, it is necessary in making fiat heads, as e, which are formed wholly within the cavity of the die, to change the slot and, instead of extending it completely across the head, form it wholly within the head, as shown at h in Fig. 8. This. change not only enables such heads to be formed by my process, but it makes the" heads stronger and more homogeneous.

It is not essential that the cavity a in the die should be conical. It may be cylindrical or globular, or the die may have a fiat surface around the hole through which the wire passes, on which the under surface of the screw-head may be formed, as clearly shown in Fig. 10. In this latter case the cavity m, for. giving shape to the head e, will be wholly formed in of the head and open at the ends, as in similar heads heretofore made, as shown in said Figs. 10 and 11.

I claim- 1. The combination of the solid die for forg' ing screw-heads with the two punches or hammers to act in succession for upsetting the metal to form the head, the first of which has the face which acts on the metal the counterpart, substantially, with the exception of the slot, of the face to be given to the screw-head, and the second of which has its face the counterpart, including the slot, of the final form to be given to the faceof the head of the screw.

2. The finishing-hammer, substantially as described, having projecting from its face a tongue with parallel or nearly parallel sides to form the slot in the metal within the cavity of a die in which a flat-faced screw-head is to be formed.

In testimony whereof I have affixed my signature in presence of two witnesses.

CHARLES D. ROGERS.

Witnesses:

CHARLES HANNIG-AN, Gno. H. REMINGTON. 

